Transcript for Americans Head to Mexico for Weight-Loss 'Balloon Pill'

It is a tantalizing notion for a weight obsessed America. What if there was one pill that would radically suppress your appetite and help you shed pounds? Sounds like a classic too good to be true scenario. Fans of this new pill called the magic bullet say it is real and it works. If you want it though you are going to have to go abroad. So we sent the chief investigative correspondent to Mexico. Nice to meet you. Hi, Kim, how are you? At 330 pounds, 4-year-old kimmy G. Says she is never full. But I did eat one before that. We are not going to talk about that. Reporter: She has tried every diet, every weight loss regime. Still nothing seems to work. And in another sunny suburb of Los Angeles, we met Dr. Daisy martin. I gained 10 pounds after getting married. I gained 20 pounds after having a baby. So I feel like I have 30 pounds that have just, has not moved since I was in my 20s. Reporter: Both women recently heard of a new capsule, a magic bullet, to help in their fight to lose weight. One that claims the kind of results that so far only invasive surgery has produced. And it is not just for the severely overweight. Are you nervous? I think I am excited. You are. I am excited I don't want the gastric bypass or lap band. I am heavy. Reporter: Why not? Cutting your stomach is not really the issue. The issue is right here. That's the main issue. Just kind of a jump-start. Reporter: Or in kimmy's case, a restart. This is when I won. A few years ago she was a successful plus-sized model even appearing in the movie. Her goal is to lose about 60 pounds, nothing more. Reporter: You would look to go back to modeling. Yes, it would be great. I still was heavy. I was thick. I felt better. I can move around better and wear good clothes. Reporter: That's what your plan is then? That's my plan. Reporter: But the plan isn't that simple. Why is it making you nervous? Jumping the border. Going over there. This is exciting. I've mean, I'm going to a dif rn ferent country to get the procedure. You haven't been able to eat for 12 hours. It is worth it. Reporter: The capsule isn't available yet in the U.S. So patients like kimmy and daisy must drive across the Mexican border to Tijuana, Mexico. A bustling city with a rap for violence and crime. This is it. This is the border. Are you serious? Yeah. Reporter: Every year thousand of Americans cautiously flock there in search of cut rate medical care. The capsule is a controversial device called obolong. Once it enters the stomach it is inflated into a small balloon. Patients feel full immediately. Here you go. We finally arrive at obesity control center in Tijuana where kimmy meets a new friend. Is it painful? No. Reporter: Gloria is a Tijuana native and took the pill three months ago and has lost 25 pounds. Both women are here to meet this man. Dr. Ortiz, a Mexican surgeon who was born and raised in Tijuana. The morning starts early. Reporter: Obolong patients helped research the capsule. Ask me what is the benefit of working in Mexico -- I get to decide the quality of health care I provide to my patients. Reporter: He lives in San Diego, every day he heads to his clinic in Tijuana where 70% of his patients are American. His staff fields more than 100 phone calls a day from patients wanting to know more about the balloon pill. Buenos dias. How is everybody doing? Reporter: Most are American as well. We're going into the operating room. Reporter: They come to him not only for the capsule but for other treatments that are approved in the U.S. But cheaper here in Mexico. Patients like kimmy will save thousand of dollars by getting the balloon which goes for $4,000, a fraction of what a gastric bypass surgery goes for. It is very intrusive. I wouldn't want to go through this. I agree. I believe one day, what we are doing now is going to be seen as barbaric. Reporter: There is another crucial difference. Daisy. Reporter: Unlike gastric by pass, the bill isn't just for the morbidly obese. This is a device. The capsule. Reporter: The pill comes with its own set of strict guidelines. This is exactly the size of-- the balloon that you are going to have. Patients won't be able to eat solid foods for the first three days. And for 12 weeks they have to commit to working out 90 minutes a day. You are going to be losing weight. You are going to be losing fast. Reporter: Once daisy starts to eat food she won't be able to eat more than a small plate of food a day. The capsule is so new there is no consensus yet in the American medical community about it. But plenty of intrigue. I would have to say, sounds interesting, I want to know more. See bariatric surgy is effective and should be a last resort. He teaches weight management. He says sustaining weight loss after the pill comes out is a concern. The stomach is a hormone producing organ. And surgery influences the hormone, that's part of the effect of the surgery. Does the balloon do that, rival the effects of surgery. What happens when the balloon goes away. Effects of the surgery for the most part are permanent. If you have a balloon put in your stomach to make you eat less and you lose weight, are you then dependent on that balloon for the rest of your life? Back in Mexico we check in with daisy and kimmy as they get ready to swallow the capsule. Both on different end of the weight loss spectrum. One who need gastric by pass. And the other who could easily lose 30 pounds with diet and exercise. Don't force the swal low. It has to go down nice and easy. Reporter: It is harder than it looks. It's weird. She tries again. If the won't through. Perfect. Wait a little bit. Reporter: Now it is kimmy's turn. There you see the bubble inflating in kimmy's stomach. See the half moon right there. And kimmy was well, pretty happy. The pill is suppose to be removed after three months. Remember, Gloria, she has had the balloon in her stomach for four months already. So the doctor might want to remove the balloon, you want to keep it. I want to keep it. Maybe one more month. Reporter: Gloria gets good news. We wanted to remove the Ba lalloon today. We are going to give you more time. Reporter: If the balloon wasn't there, ooh, lord I would have ate. Daisy and kimmy kept video diaries to let us in on the progress. End of week two, beginning of week three. I lost a total of 14.whatever pounds. I have lost five pound so far. Reporter: After 30 days, daisy has lost almost ten pounds. Usually. Probably like this much. Set my stomach. And kind of keep me going. Reporter: And kimmy, a whopping 22 pounds. I went through Easter. Not going to lie, that ham was damn good, okay. I did sneak some pieces. Reporter: When the balloons come out in two months we will be there to see if they're able to keep the weight off.

This transcript has been automatically generated and may not be 100% accurate.

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